Just as regular exercise gives your body some biological benefits, mentally controlling two or more languages gives your brain cognitive benefits. This mental flexibility pays big dividends especially later in life: the typical signs of cognitive ageing occur later in bilinguals – and the onset of age-related degenerative disorders such as dementia or Alzheimer’s are delayed in bilinguals by up to five years.
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People self-report that they feel like a different person when using their different languages and that expressing certain emotions carries different emotional resonance depending on the language they are using.
When judging risk, bilinguals also tend to make more rational economic decisions in a second language. In contrast to one’s first language, it tends to lack the deep-seated, misleading affective biases that unduly influence how risks and benefits are perceived. So the language you speak in really can affect the way you think.